Time dilation

    According to Euclid, we live in a 3-dimensional world, being able to pinpoint our position using three coordinates: x, y and z. Einstein saw this in a different light- 4 dimensions. According to his special theory of relativity "The four dimensional space-time continuum of the theory of relativity , in its most essential formal properties, shows a profound relationship to the Euclidian geometrical space. In order to give due prominence to this relationship, we must replace the usual time coordinate t by an imaginary magnitude by (√-1)* ct proportional to it." Just as space is fluctuary, time changes as well.
    One feature that distinguishes time from space in how it is changed, is that motion changes time relatively. To illustrate that, imagine that an observer, person A, is on a stationary platform, and I have another person, person B, also on that platform, sitting in a spaceship. They are both experiencing, at that moment the same rate of time. Now the spaceship launches and it is accelerating. If he is traveling at 0.5c (half the speed of light) What feels like one day to person B, is 1.15 relative days for person A. As he gets closer to the speed of light, 0.99c, one day for person B is over a week back at the platform. Time goes up rapidly from there. at0.99999999999999c, for one day for person B, person A is long dead having almost 2000 years pass on his platform.
     This data is all based upon the Lorentz factor, which is represented by the equation below, with:
t = time
v = velocity
c = constant, the speed of light

 Rest Frame Time Elapsed per Day on Ship        
v/c                           Days        Years
0.0                           1.00         0.003  
0.1                           1.01         0.003  
0.2                           1.02         0.003  
0.3                           1.05         0.003  
0.4                           1.09         0.003  
0.5                           1.15         0.003  
0.6                           1.25         0.003  
0.7                           1.40         0.004  
0.8                           1.67         0.005  
0.9                           2.29         0.006  
0.95                          3.20         0.009  
0.97                          4.11         0.011  
0.99                          7.09         0.019  
0.995                        10.01         0.027  
0.999                        22.37         0.061  
0.9999                       70.71         0.194  
0.99999                     223.61         0.613  
0.999999                    707.11         1.937  
0.9999999                  2236.07         6.126  
0.99999999                 7071.07        19.373 
0.999999999               22360.68        61.262 
0.9999999999              70710.68       193.728
0.99999999999            223606.79       612.621
0.999999999999           707114.60      1937.300       
0.9999999999999         2235720.41      6125.261       
0.99999999999999        7073895.38     19380.535      
0.999999999999999      22369621.33     61286.634      
Sincerely,
Space Cadet



High-Quality Photograph of a Black Hole



Black holes are an well-known effect that is consistent with Einstein's theory. Black holes are an extremely dense region of space where even light cannot escape. The premise of this phenomena is that a massive object bends space-time. If that massive object was extremely dense, it would ultimately bend space-time so that the walls of the dent are vertical. If a light beam is traveling and encounters the black hole, it will be bent at a consistently increasing angle so that it loops back upon itself and continues circling. It is now trapped. Objects of mass can be caught in the same way. When they spiral to the center they will be crushed to extreme density.





Swartzschild Radius
Formula

A black hole is formes when a star collapses to a diameter equivelant to or past its Swartzschild Radius. The Swartzschild radius is a ratio of a spherical object's mass to its radius. The formula(left): Rs is the Radius, G is Gravitational Constant, m is the mass of the object , and c  is the speed of light in a vaccum. To put this in proportion,  if the earth were to become a black hole, the mass would have to be contained within a 9 millimeter radius. However most black holes are not quite as small. The chart below shows a few examples of their massive size:

sincerely,

Space Cadet

Gravitational lensing



Einstein's Cross- example of lensing.

 Einstein's Relativity theory allows for certain effects that would not be possible according to the Newtonian theory. Because Gravity does not involve a force, massless objects can be affected. A straight beam of light, passing by a dent in space-time caused by a object of mass, will be bent to follow that geodesic path. The implication of this is a phenomena called gravitational lensing.

The main idea of Gravitational Lensing is if a massive object is in front of a star, or other bright object, the rays from the star will be bent around the massive object, appearing to the observer to be two or more distinct objects.

This is far from being just an interesting effect. Using geometry, one can derive the approximate distance of the object. Also Astronomers are using gravitational lensing to predict the placement and size of pockets of dark matter, as it also bends light.
Sincerely,
Space Cadet

Newton and Einstein- Gravity

     In 1916, Einstein published his theory of General Relativity, radically changing the way we view gravity. Over 200 years earlier, Newton published his "law of universal gravitation" in Principia Mathematica. Newton's view of gravity held that gravity was a force. This force is the attraction of mass to mass, the larger mass having a stronger pull on the smaller mass, and the smaller mass pulled upon the larger with less force. To this day Newton's gravitational equation is used to approximate a given object's weight upon a given planet.

 However, Einstein saw gravity in a different light. He supposed that mass could bend the fabric of space-time, much like a bowling ball on a trampoline. A smaller mass, like a planet, would simply follow the geodesic curve in an acceleration percieved as a force.

Since 1916, Einstein's theory has been shown to be accurate over the years, as certain  points are proven, such as the GP-B probe and the proof that gravity acts at the speed of light. His theory also covers other important points (such as Gravitational lensing) to be mentioned in a later post.

Sincerely,

Space Cadet

Gravity Probe B - Testing Einstein's Theories

Gravity Probe B has tested- and proven,  two effects of the general relativity theory developed by Albert Einstein developed in 1916. Orbiting around the earth, the spacecraft has the perfect opportunity to measure this, as the earth itself is a large enough mass to warp space-time noticably. The sensitive gyroscopic sensors were able to prove:
"1.The geodetic effect—the amount by which the Earth warps the local spacetime in which it resides.


2.The frame-dragging effect—the amount by which the rotating Earth drags its local spacetime around with it."(GP-B Mission)
The Geodetic effect is an essential component of the General Relativity theory, as it rests upon the tenet that mass can warp space-time. This allows for the existence of black holes, quasars, and other space phenomena.
The frame dragging effect had never been tested before. It can be visualized as a ball spinning in a bowl of a thick liquid such as syrup. As it spins it drags the syrup in a spiral around it.
In theory testing relativity is a simple concept. According to GP-B Mission;
 
"1.Place a gyroscope and a telescope in a polar-orbiting satellite, 642 km (400 mi) above the Earth. (GP-B actually uses four gyroscopes for redundancy.)


2.At the start of the experiment, align both the telescope and the spin axis of each gyroscope with a distant reference point—a guide star.

3.Keep the telescope aligned with the guide star for a year, as the spacecraft makes over 5,000 orbits around the Earth, and measure the change in the spin-axis alignment of each gyro over this period in both the plane of the orbit (the geodetic precession) and orthogonally in the plane of the Earth's rotation (frame-dragging precession).

The predicted geodetic gyro-spin-axis precession is a tiny angle of 6,606 milliarcseconds (0.0018 degrees) in the orbital plane of the spacecraft. The orthogonal frame-dragging precession is a minuscule angle of 39 milliarcseconds (1.1x10-5 degrees). "
Links:
Official Site
NASA GP-B Mission
Paper model of the Spacecraft

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Sincerely, Space Cadet

50th Anniversary of Human Space Flight

     The 12th of April marked the 50th anniversary of human spaceflight. On that day in 1961 Yuri Gagarin, a soviet Military Pilot, became the first human to orbit the earth. This event had a lot of political implications, as it seemed the Russians would beat the Americans in the dominance of space. Previously the Russians had already put the first satellite, sputnik 1, and the first animal, a dog named Laika (literally translated means "Barker") . All of these victories to the Russians. were a major blow to the Americans and their pride. The Americans caught up soon, and ultimately won the race to dominate space in 1969 as Neil Armstrong stepped upon the moon.
Sincerely, Space Cadet

Update on the MESSENGER- found Mariner 10 spacecraft

The messenger team was surprised to notice a strange object in one of the photos that the Messenger spacecraft sent back today(April 1st). The image, first thought a imaging artifact, upon close examination was recognized as the Mariner 10. The Mariner was a space probe that was sent in 1973 to swing by mercury and take photos. The space probe visited mercury 3 times, then lost contact. It was not heard of until today. However, based upon its orbit it should not have been near mercury at this time. It is calculated that the space probe's orbit as altered by changes in solar radiation and multiple outgassing events by the residual propellant caused changes in the trajectory of the probe. It does not appear that the probe will be in the way of the messenger in the next few orbits.
Sourced:messenger.jhuapl.edu

MESSENGER- Historic Mercury Photographs

Yesterday, March 29, a historic photo of mercury was taken by the Messenger spacecraft.The Messenger is the first orbiting satellite around Mercury. Its first photo of the terrain was recieved on earth March 29.  Previous photos of Mercury had been taken by the Mariner, though the Mariner program was just a flyby. Currently the spacecraft has sent back to earth over 300 photos, and is working on global mapping of the planet. According to wikipedia, "the mission is designed to clear up six key issues: Mercury’s high density, its geological history, the nature of its magnetic field, the structure of its core, whether it has ice at its poles, and where its tenuous atmosphere comes from."
More info:
NASA Messenger 
MESSENGER official site

 

Albatros D.I

The German Fokker E-1 paved the way for more advanced fighters during WWI. the Fokker company produced more of the E series, continuing the synchronized machine gun with the propeller. However the Allied forces had built the Airco D.H.2 and the Nieuport 11 which proved to be superior to the E series in combat. As a response, the Germans employed the Albatros D1. This plane had a different design, consisting of a single shell around minimal interior structure. This lightened the load, and increased the effectiveness of the aerodynamic surfaces. The D1 was not as good in manuvering, but had superior fire power and speed (110 mph ) giving it superiority over the planes of the allied forces.
Specifications (from wikipedia)

• Crew: one pilot
• Length: 7.40 m (23 ft 3.5 in)
• Wingspan: 8.50 m (27 ft 11 in)
• Height: 2.95 m (9 ft 8 in)
• Wing area: 22.9 m² (247 ft²)
• Empty weight: 645 kg (1,422 lb)
• Gross weight: 898 kg (1,809 lb)

Performance

• Maximum speed: 175 km/h (110 mph)
• Endurance: 1.5 hours
• Service ceiling: 3,000 m (9,840 ft)
• Rate of climb: 2.8 m/s (547 ft/min)

Armament

• 2 × forward-firing 7.92 mm (.312 in) LMG 08/15 machine guns

Fokker E-1

Airplanes, previously viewed as "toys", gained new meaning during WWI. A battle was found to be more effective with a reconnaissance mission carried out by a scout plane, though due to the weight that the early airplanes could handle, bombs were not much of an option until planes that could handle larger loads were built. One of the first true armed aircraft, meant for aerial combat was built by the Germans, the Fokker E-1. It was the first plane to mount the machine gun on the front of the aircraft, positioned behind the propeller. It synchronized the firing of the gun with the rotation of the propeller.

The Fokker E-1 was designed to roll using wing warping via acables attached to the wing. The plane was built of welded steel tubes, covered in fabric. It had a single machine gun, a 7.92 mm Parabellum LMG 14 or Spandau LMG 08 machine gun, affixed to the front of the aircraft, behind the propeller. It was employed to the Fliegertruppe of the German Army.

The Fokker E-1 was an important stepping stone in the development of fighters. More advanced fighters were developed and used by many countries during WWI.

Specifications (from Wikipedia)

Fokker E-1

• Crew: one, pilot

• Length: 7.22 m (23 ft 7 in)

• Wingspan: 8.85 m (29 ft 0 in)

• Height: 2.9 m (9 ft 5½ in)

• Wing area: 15.9 m² (172.2 ft²)

• Empty weight: 360 kg (789 lb)

• Loaded weight: 563 kg (1,241 lb)

• Powerplant: 1× Oberursel U.0 7-cylinder air-cooled rotary engine (clone of Gnôme Lambda engine) using various makes of 2-blade propellers, from 2.3 to 2.5 meters (7.55 to 8.20 ft) diameter, 80 hp (60 kW)

Performance

• Maximum speed: 130 km/h (81 mph)

• Range: 198 km at 110 km/h (123 mi at 68 mph)

• Service ceiling: 3,000 m (9,840 ft)

• Rate of climb: 20 min to 2,000 m (6,560 ft)

Armament

• 1 × forward-firing 7.92 mm (.312 in) Spandau lMG 08 machine gun (one Parabellum MG14 M/G on prototypes

Sincerely, Space Cadet

New Changes for the space program

In 2010 President Barack Obama announced new goals for the American Space Program. These change how we, as Americans, will dominate space, and also where our money goes. Some of these new goals will improve the space program, whereas others may be have a devastating effect on the American Space Program.
One of the most controversial changes to the space program was the cancellation of the Constellation program (CxP). According to three Apollo Astronauts,Neil Armstrong, James Lovell and Eugene Cernan, this “decision to cancel the Constellation program, its Ares 1 and Ares V rockets, and the Orion spacecraft, is devastating.”1 The constellation program was designed to keep an American foothold in the frontier of space, to return to the moon and possibly mars. However, President Obama said the program is "behind schedule, and lacking in innovation"2. The cancellation of the CxP has a lot of political implications because we have to rely on the International Space Station (ISS). The ISS is a result of international partnership with other nations, particularly Russia. According to the agreement we made with the Soviet Nation we have to pay a fee to Russia for the seat in space.
Not all changes to the space program are negative. One positive change will be the use of private industry for crew and cargo services to the International Space Station. In 2004 Astronaut Mike Melville successfully flew Space Ship one into space. Not only did he win the X-prize, but launched a new age of space travel- Private Investors. Companies such as Space-X are now entering the field of space. Now, with access to the ISS, Private Companies are taking another step into this frontier. I believe this is a positive investment. Through these companies America may still keep their name in Space.
The President is also putting a new focus onto Green Aviation. NASA researchers have recently, as of September 21st, resumed working on the X-48b. This has a Blended wing body designed specifically for that purpose. The Blended Wing Body is a plane design, where the entire plane is a lifting surface. This design is less noisy and more fuel efficient than it's predecessor, the tube design. This plane is controlled by a pilot on the ground, via cameras in the front, The design will be integrated into future airliners.
Also included in the new plan is a new focus on robotic space exploration. This program will send a series of robotic missions to explore the solar system. These robots will pave the way for future manned spaceflight. However, with the cancellation of the CxP, it will take much longer, and will take more money, to get us on other planets.
NASA will be putting a new focus on education, through the STEM Program. STEM stands for Science, Technology, Engineering and Mathematics. Through STEM, NASA will educate students of all ages, and teachers. Some of these students may become NASA's future, working to keep the American Space Program alive.
The new changes to NASA's goals will change the future of the american space program. Some changes are positive. Our Nation will have “quieter, cleaner, and more fuel-efficient airplanes for the future.”3 because of new technology being developed. Students are being educated through STEM to help keep our space program alive. Private Space companies will keep us in space. However some changes are for the worse, such as the cancellation of the Constellation Program. This “devastating” blow to NASA will be a backwards step in our foothold in the space frontier.
Quotes:
1 http://www.msnbc.msn.com/id/36470363
2 http://news.bbc.co.uk/2/hi/science/nature/8489097.stm
3 http://www.nasa.gov/centers/dryden/status_reports/X-48B_status_09_21_10.html
Sources:
http://newfrontiersblog.blogspot.com/search/label/constellation
sincerely, space cadet

Blended wing Bodies- the plane of the future

Research in the fields of Aerodynamics has increased our knowledge of flight and how to design better wing surfaces. This Knowledge is being put into action by the NASA Engineers. The engineers integrated a Blended wing Body in their design, successfully creating the X-48b, a step forward in creating "quieter, cleaner, and more fuel-efficient airplanes for the future"(NASA)

The Blended Wing Design means that the entire plane is a lifting surface, not just the wings.

This design has several advantages. The design is less noisy, so people will not be as bothered living in a house by an airport. It has better lift and uses less fuel, which may decrease the price on your plane ticket.I

However, there is no such thing as a free lunch. Disadvantages come in the package. Because of the positioning of the cargo, which creates less flight stability than the tube design. The tube design is more structurally sound than the x-48b. Also windows are not available, due to the entire plae being a wing.

Despite these disadvantages, this plane could be the aircraft of the future. As this experimental plane is unmanned, being remote controlled by a pilot on the ground, it's design will be incorporated into airliners in the near future.

Sincerely, Space Cadet

Railguns

Railguns are a topic that have been included in countless Sci-Fi media. The American Department of the Navy has been working to make this idea a reality.
What is a Railgun? It is a "Weapon, consisting mainly of conducting metal rails, that uses electromagnetic force to accelerate a projectile to a much greater speed than achieved"
It was idealized as the "perfect weapon". Using electromagnetic propulsion would eliminate the need for ammunition, thereby making a much safer ship to sail on. Making it a reality was much harder than expected. The projectile moved so fast that the friction melted the gun. Once they fixed that problem, the projectile vaporized when it entered the atmosphere. Also they had to solve the problem of power. The Navy is designing a new battleship so that the power will be derived from the main engine.
Dec 10, 2010 the NAVY succesfully launched the projectile through the railgun at Naval Surface Warfare Center Dahlgren Division. At launch the projectile had 33 Megajoules- 1 Megajoule is the equivalent of a 1-ton ar traveling a 100 mph. It demolished the target at impact an set the guinness world record for most energy upon launch. Much more than had been achieved by ammunition.
Sincerely, Space Cadet